221
FXUS66 KOTX 100903
AFDOTX
Area Forecast Discussion
National Weather Service Spokane WA
203 AM PDT Tue Jun 10 2025
.KEY MESSAGES...
- Moderate to major Heat Risk continues through Tuesday.
- Dry and breezy with elevated to critical fire weather
concerns Monday through Thursday.
- Cooler but still warm and mountain thunderstorms mid to late
this week.
&&
.SYNOPSIS...
Very warm temperatures continue Tuesday. Breezy winds and dry
conditions today through Thursday will lead to increased fire
weather concerns. Temperatures will gradually cool down starting
Tuesday and mountain thunderstorm chances begin to increase
Wednesday.
&&
.DISCUSSION...
Today through Friday night: There is very good agreement among the
model ensembles through the rest of the work week. The ridge of high
pressure over the Northwest will begin to flatten today with the
flow aloft becoming zonal. Winds aloft will strengthen a bit as
the jet stream migrates more over the region. Today will be another
warm day, but temperatures aloft will cool slightly with record
highs not as likely to be broken. Hot temperatures in the
Columbia Basin topping out in the mid to upper 90s will once
again create a thermal gradient across the Cascades that will drive
a push of westerly winds through the Cascade gaps for the late
afternoon and evening. These gap winds with continue dry conditions
will be conducive for another day of critical fire weather
conditions in the Wenatchee Area and Waterville Plateau. It was
bright and sunny west of the Cascades on Monday indicating a dry air
mass all the down to the surface. The flattening of the ridge will
increase the onshore flow Wednesday into Thursday, and this will in
turn result in a deepening marine layer. A push of marine air will
will be felt, particularly on Thursday when the marine layer looks to
finally deepen enough for moisture to spill through the Cascade
gaps. A deepening marine layer will act in concert to the westerly
pressure gradient resulting in a greater push of air and breezier
winds. Winds today will be similar to Monday with the Wenatchee Area
expected to see winds of 10-20 mph with gusts up to around 30 mph.
Then a slight uptick Wednesday and Thursday with these same areas
more likely to see gusts closer to 35 mph. A more in-depth discussion
on the fire weather conditions each day this week is discussed in
the Fire Weather section of the AFD below.
Temperatures will see a gradual cooling trend this week as the
marine layer deepens each day. With a noticeable relief in the warm
temperatures by Thursday into Friday as highs dip back into the 80s
and 70s respectively. These temperatures will remain above normal
for mid June, but much closer to what we expect for this time of
year. Increased moisture into the region will introduce the
potential for the atmosphere to destabilize with diurnal heating in
the afternoon. Chances for convection will be low below 25% chance
for showers mainly over the mountains near the Canadian border
starting Wednesday, and that potential continuing each afternoon
into the weekend. There is potential for convection over northeast
Oregon as well, but there looks to be enough westerly flow to keep
this threat from migrating into easter Washington and largely off to
the south and east.
Saturday through Monday: Ensembles diverge a little bit in the far
extended. There is overall good agreement that a trough of lower
pressure will dig in over the region, but there is uncertainty in
the strength of this trough. Roughly 55% of the ensemble members has
a deeper trough digging in with roughly 40% of those members closing
off a low off the WA/OR coastline before pushing onshore. Closing
off the trough would increase the potential for wrapping in moisture
over the Inland Northwest and give the region a shot at what is
desperately needed precipitation. There`s a 10-20% chance for at
least a tenth of an inch of precipitation across north-central
Washington from Monday night through Tuesday. These probabilities
increase to a 30-40% chance in the Idaho Panhandle. There is a
varying degree of precipitation amounts with the deeper trough
scenario. The other 45% of the ensemble members indicates a much
weaker trough swinging across. This scenario paints a much drier
scenario. Temperatures continue to cool a bit, but chances for
seeing wetting rains would be bleak. I`m not holding my breath that
we`ll get a wet and cool period by the beginning of next week, but
I`m saying there`s a chance! /SVH
.FIRE WEATHER...
The ridge of high pressure over the Inland Northwest delivering hot
and dry conditions will flatten over the next few days. This will
bring the potential for increased westerly winds by Wednesday and
Thursday through the Cascade gaps and out over the Columbia Basin.
Today will be a near repeat to Monday expect temperatures won`t be
as hot. A similar surge of westerly winds can be expected through
the Cascade gaps and out across the Waterville Plateau and across
the Columbia River out of the Kittitas Valley into Vantage and
George. Winds look to increase again between 1600-1700 PDT and
remain breezy into the evening hours. Although temperatures will be a
few degrees cooler today, dew points will be drier and this will
equate to even lower minimum relative humidity values down into the
lower teens and possibly into the single digits. Relative humidity
will also be slow to recover today and may be until 2200 PDT before
recovering above 20%. A red flag warning remains in effect for
Tuesday for breezy winds and low relative humidity between 1500 and
2100 PDT. The surge of westerly winds will be a bit stronger
Wednesday and Thursday as the marine layer deepens over this period
supporting at least a slightly stronger surge through the Casca1918,2025des.
Both of the these days will also need to be monitored for the
potential of critical fire weather conditions, but confidence isn`t
high enough at this time to expand the red flag warning past today.
/SVH
&&
.AVIATION...
12Z TAFS: VFR conditions will prevail. West to northwest winds
at KEAT increase to between 10-15 kts across the Columbia Basin
as well Tuesday afternoon impacting KMWH-KGEG-KSFF-KPUW
terminals.
FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence
for VFR conditions. Conditions will be right for critical fire
weather conditions in the afternoon and evening near KEAT to
KWMH that may result in fires that impact these terminals
through Wednesday.
-----------------------
Confidence descriptors:
Low - Less than a 30 percent chance
Moderate - 30 to 70 percent chance
High - Greater than a 70 percent chance
For additional probabilistic information for NWS Spokane airports,
please refer to the Aviation Dashboard on our webpage:
https:/www.weather.gov/otx/avndashboard
&&
.Preliminary Point Temps/PoPs...
Spokane 92 58 86 56 81 53 / 0 0 0 10 10 10
Coeur d`Alene 91 58 86 55 81 53 / 0 0 10 10 10 20
Pullman 87 56 81 51 77 49 / 0 0 10 10 0 20
Lewiston 98 64 91 57 87 59 / 0 0 10 10 10 20
Colville 92 52 88 51 81 47 / 0 0 10 20 30 30
Sandpoint 90 56 86 54 81 51 / 0 0 10 20 20 30
Kellogg 88 62 83 55 79 56 / 0 0 10 20 10 30
Moses Lake 98 59 94 57 87 51 / 0 0 0 0 0 10
Wenatchee 97 65 92 60 84 55 / 0 0 0 0 0 10
Omak 95 59 92 59 84 52 / 0 0 10 20 20 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Heat Advisory until 9 PM PDT this evening for Central Chelan
County-Lower Garfield and Asotin Counties-Northeast
Mountains-Okanogan Highlands-Okanogan Valley-Spokane Area-
Upper Columbia Basin-Washington Palouse-Waterville
Plateau-Western Chelan County-Western Okanogan County.
Extreme Heat Warning until 9 PM PDT this evening for Moses
Lake Area-Wenatchee Area.
Red Flag Warning from 3 PM this afternoon to 9 PM PDT this
evening for Foothills of Central Washington Cascades
(Zone 705)-Waterville Plateau (Zone 706).
ID...Heat Advisory until 9 PM PDT this evening for Central
Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
Lewiston Area-Northern Panhandle.
&&
$$